This invention relates to novel optically active compounds useful as reagents for asymmetric synthesis such as chiral auxiliaries and chiralsynthon.
An optically active diol is very useful as a reagent for various asymmetric synthesis such as asymmetric source in the synthesis of optically active acetal or chiral auxiliary in a diastereo-differentiating Simmons-Smith reaction. The most representative compound among optically active diols heretofore used as a reagent for asymmetric synthesis is 2,4-pentanediol (hereinafter referred to as PD). Optically active PD, however, has a comparatively low melting point of 50.5.degree. C. In addition, it has very high moisture absorption property and can be hardly dried. Therefore, it is difficult to handle. Further, it possesses problems particularly when it is used for an anhydrous reaction. Accordingly, a novel optically active diol has been desired which is free from the above problems and has excellent properties as a reagent for asymmetric synthesis.